GNU bug report logs - #46808
Man page of "tail"

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Message #16 received at 46808 <at> debbugs.gnu.org (full text, mbox):

From: Brendan O'Dea <bod <at> debian.org>
To: Reuti <reuti <at> staff.uni-marburg.de>, 46808 <at> debbugs.gnu.org
Cc: Paul Eggert <eggert <at> cs.ucla.edu>
Subject: Re: bug#46808: Man page of "tail"
Date: Thu, 24 Feb 2022 21:44:28 +1100

On Thu, Feb 24, 2022 at 12:02:55AM +0100, Andreas Schwab wrote:
>On Feb 27 2021, Reuti wrote:
>
>> I'm not a `groff` expert, but the sequence "\,some-text\/" appears a couple of times. What effect does it have for the formatting as the "," and "/" are not output?
>
>\, and \/ add some space as italic correction, see (groff) Ligatures and
>Kerning.

https://www.gnu.org/software/groff/manual/html_node/Ligatures-and-Kerning.html

Note that these escapes are a no-op when manual pages are formatted for
a terminal (e.g. running "man tail" and viewing the output in a pager).

They are added to improve output rendered for printing (ps, pdf, dvi,
etc):

  man -t tail | lpr -Pps
  man -Tpdf tail >tail.1.pdf

As Paul noted, those escapes and other formatting are added by help2man,
using a heuristic which mostly works, but seems a bit hit and miss with
some of the tail flags: "--bytes=[+]NUM" as you identified doesn't fare
well.  Compare to ls flags "--block-size=SIZE" and "--color[=WHEN]".

I'll take a look to see if I can do something to handle tail's output
better.

--bod

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